Therapeutic combination silencing VEGF and SOX10 increases the antiangiogenic effect in the mouse melanoma model B16-F10 - in vitro and in vivo studies.

INTRODUCTION: Gene therapy is an innovative form of treatment of genetic diseases, in which psiRNA molecules silencing specific genes are applied. AIM: The study evaluated the anti-tumour effect of psiRNA silencing preparations of the vascular endothelial growth factor (VEGF) and Sry-related HMG-Box gene 10 (SOX10) on melanoma (B16-F10) by inhibiting angiogenesis. MATERIAL AND METHODS: The preparations based on plasmid vectors psiRNA silencing the gene SOX10 and VEGF that form complexes with cationic lipid (psiRNA/carrier) have been developed. psiRNA preparations were tested on the mouse melanoma cell line B16-F10, both in vitro and in vivo. The silencing activity of transfected melanoma cells with the obtained psiRNA preparations was examined using the qPCR and Western blot methods. The anti-tumour activity of psiRNA preparations on melanoma tumour cells was then evaluated in a mouse in vivo model. RESULTS: In vitro studies have shown that the B16-F10 cells efficiently transfect non-viral preparations - psiRNA: Lyovec (74-89%). Worth mentioning is the fact that silencing SOX10 in B16-F10 melanoma cells increases the expression of the COL18A1 gene (compared to the preparation inhibiting only VEGF), which codes the endostatin to stop angiogenesis. In vivo results show that the level of haemoglobin in tumours of mice treated with psiRNA formulations was over 6 times lower than controls and tumour mass was 60-80% lower. CONCLUSIONS: The novel study proves that simultaneous inhibition of SOX10 and VEGF enhances the antiangiogenic action and thus contributes to a significant halt of disease development. In addition, these data expand knowledge about SOX10 regulation and functions.

Resistance of melanoma cells to anticancer treatment: a role of vascular endothelial growth factor.

Melanoma is one of the most aggressive and resistant to treatment neoplasms. There are still many challenges despite many promising advances in anticancer treatment. Currently, the main problem for all types of treatment is associated with heterogeneity. Due to heterogeneity of cancer cells, "precise" targeting of a medicine against a single phenotype limits the efficacy of treatment and affects resistance to applied therapy. Therefore it is important to understand aetiology and reasons for heterogeneity in order to develop effective and long-lasting treatment. This review summarises roles of vascular endothelial growth factor (VEGF) that may stimulate growth of a melanoma tumour irrespective of its proangiogenic effects, contributing to cancer heterogeneity. VEGF triggers processes associated with extracellular matrix remodelling, cell migration, invasion, angiogenesis, inhibition of immune responses and favours phenotypic plasticity and epithelial-mesenchymal transition. Consequently, it participates in mechanisms of interactions between melanoma cancer cells and microenvironment and it can modify sensitivity to therapeutic factors.

Peritoneal fluid stimulates neoplastic transformation of normal HEK 293 cells by high expression of pluripotent genes.

Gynecological cancers constitute a serious problem in the world. Their advanced stages are often characterized by the accumulation of ascites, which leads to spreading of cancer cells outside their primary focus. Despite progress in the treatment, prognoses are still not satisfactory. The main causes of these failures are chemoresistance, metastases and recurrences of the disease, which is influenced by, among others, the microenvironment of cancer cells. This study investigated the effect of the microenvironment, which create ascites derived from patients with ovarian and endometrial cancer to non-gynecological HEK 293 cells. The effect of the gynecological cancer microenvironment on HEK 293 cells behaviour was analysed using RT-PCR, qRT-PCR, Western blotting and functional analysis (invasion assays, hanging drop) methods. Our results suggest that the key genes for the development of cancer can be regulated by epigenetic and hypoxia-inducible factor in dependent manner. It was observed that in vitro microenvironment, which is created by cells originating from patients with gynecological cancer (ovarian cancer, endometrial cancer) is able to generate changes in HEK 293 cells by itself.